While not all my handlers problems are Psychiatric, Many people question weather a dog can be classified as an emotional support dog or a Psychiatric Service dog. An Emotional Support dog does not need to generally be trained beyond basic things such as potty training. A service dog is a specially trained dog to help someone with a disability. A Service Dog is trained in what are called Tasks to specifically help with a disability as well as to access places beyond home, vs emotional support or comforting which aren’t trained in a command or task to help someone with a disability. Generally people who use / require Psychiatric service dogs need more then just medications and therapy to help with their issues. They must be able to prove they have a Disability. People who are Disabled generally have difficulty doing everyday tasks and living independantly. Service Dogs are trained to do tasks a Handler cannot do (Or have severe difficulties doing) on their own.
For more Information on The differences you can check this page out here.